What are opiates?

Opiates, originally derived from the opium poppy, have been used for thousands of years for both recreational and medicinal purposes. The most active substance in opium is morphine - named after Morpheus, the Greek god of dreams. Codeine, a less powerful drug, is also found in opium. Both these opiates relieve pain, relax muscles and cause drowsiness. All opiates mimic your body's own painkillers. Morphine is a very powerful painkiller, but it is also very addictive.